In particular, the present invention relates to a tire building device of the type including a unistage drum in turn including an inner shaft; two half drums mounted in a sliding manner on the inner shaft and designed to move in relation to each other between an open idle position and a closed operating position; expandable clamping means on each half drum for clamping a respective bead; and a number of annular bladders on each half drum, selectively inflatable with pressurized fluid.
Co-pending U.S. patent application Ser. No. 07/832,158, filed concurrently herewith and which is incorporated herein by reference in the interest of full disclosure, pertains to a method and device for joining stratified or layered tire portions or components by means of an innerstitching operation, during which the inner carcass of a green tire and the outer tread belt are assembled together inside a fixed stitching mold, in one embodiment, by rotating stitching devices over the inner surface of the carcass. The stitching devices push the carcass radially outwardly so as to adhere perfectly to the tread belt, which in turn is pushed against the inner surface of the mold in contact with which the finished green tire is accurately formed.